Mass of chair on weighing scale and wall

AI Thread Summary
The problem involves a chair resting on a weighing scale and a wall, with the scale reporting different weights when upright and upside-down. The upright weight is 42.62 kg, while the upside-down weight is 26.82 kg. The chair contacts the scale at a specific angle and distance from the wall, with given friction coefficients for both surfaces. The calculations suggest that the total force acting on the system can be used to determine the mass of the chair, resulting in an estimated mass of 69.44 kg. The discussion raises questions about the correctness of the approach and whether all provided information is necessary for the solution.
dmouthfan2028
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For what it's worth, I came up with this problem, so perhaps it cannot be solved, or there could be a way to solve it without using all of the information given.

Homework Statement
A chair rests on a weighing scale and a wall. The relevant surfaces of the scale and the wall are perpendicular to each other. When upright, the scale reports 42.62 kg as its weight, but when flipped upside-down, the scale reports 26.82 kg. The chair makes contact with the scale at 0.4 m from the wall at an angle of 64 degrees. Frictional coefficient between the chair and the wall is 1.02, and between the chair and the scale is 1.16. What is the mass of the chair?
 
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dmouthfan2028 said:
When upright, the scale reports 42.62 kg as its weight...

A correction:
When upright, the scale reports 42.62 kg as its mass...
 
Have I figured it out? Is this correct?

F_{gOnScale} = 42.62*9.81
F_{gOnWall} = 26.82*9.81
F_{T} = F_{gOnScale} + F_{gOnWall} = 42.62*9.81 + 26.82*9.81
F_{T}/a_{g} = \frac{42.62*9.81 + 26.82*9.81}{9.81} = 69.44\text{ kg}
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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